package main

import (
    "flag"
    "fmt"
    "github.com/gorilla/websocket"
    "log"
    "net/http"
)

var upgrader = websocket.Upgrader{
    CheckOrigin: func(r *http.Request) bool {
        return true
    },
}
var addr = flag.String("addr", "localhost:8080", "http service address")
var clients = make(map[*websocket.Conn]bool)

func main() {
    flag.Parse()

    http.HandleFunc("/", echo)

    err := http.ListenAndServe(*addr, nil)

    if err != nil {
        log.Println(err)
    }
}

func writeMessages(message *[]byte) {
    for conn, active := range clients {
        fmt.Println(active)
        err := conn.WriteMessage(1, *message)

        if err != nil {
            log.Println(err)
        }
    }
}

func echo(w http.ResponseWriter, r *http.Request) {
    conn, err := upgrader.Upgrade(w, r, nil)

    clients[conn] = true

    if err != nil {
        log.Println(err)
    }

    for {
        mt, message, err := conn.ReadMessage()

        if err != nil || mt == websocket.CloseMessage {

            break
        }

        go writeMessages(&message)
    }

    delete(clients, conn)
    err = conn.Close()

    if err != nil {
        log.Println(err)
    }
}